Scientists set off hand dryers in the bathrooms and placed a special plate just beneath them for 30 seconds.

After testing the plates, they showed between 18 and 30 colonies of bacteria on them.

How do fecal particles end up in a hand dryer?

Essentially, when you flush a toilet with its lid off, this sends fecal particles whizzing through the air.

Hand dryers tend to suck these up, warm them up, and spit them right out again.

“These results indicate that many kinds of bacteria, including potential pathogens and spores, can be deposited on hands exposed to bathroom hand dryers, and that spores could be dispersed throughout buildings and deposited on hands by hand dryers,” the study concluded.

To avoid that bacteria, the researchers suggested fitting hand dryers with HEPA filters, which could reduce bacterial deposition fourfold, or switching to paper towels — though that solution isn’t particularly environmentally friendly.